The present invention is drawn to a retaining clip useful in forming a xe2x80x9cblindxe2x80x9d connection between a first panel and a second panel.
When making a blind connection between a first panel, typically the sheet metal framework of an automobile or the like, and a second panel, often an interior panel of the same automobile, it is well-known to use a simple metal retaining clip that can be received within a window or aperture formed through the first panel and that will engage therein a fastener that extends from an undersurface of the second panel. Such prior art metal retaining clips are deficient in that the abrasive nature of the metal retaining clips often wears through the paint or anticorrosive coatings of the primary panel, thereby promoting corrosion. In addition, metal retaining clips have a distinct tendency to buzz, squeak, and rattle, a condition typically referred to as BSR. In an effort to reduce or eliminate BSR and to prevent corrosion, plastic fasteners have been used to replace the prior art metal retaining clips. Unfortunately, these plastic retaining clips tend to be relatively complex, require complex tooling and molding operations, and have moderately high insertion forces required to seat a blade fastener therein.
In light of these deficiencies, it would be desirable to provide a retaining clip that may be constructed of non-abrasive materials such as plastic and the like using relatively simple and inexpensive molds and which has a relatively low insertion force.
The present invention is realized in a retaining clip having a U-shaped body with a pair of legs that are flexibly connected at their bottom ends. These legs are spaced apart sufficiently to receive therebetween a blade fastener that typically extends from the backside of a panel that is to be assembled with yet another panel, such as where the interior panels of an automobile are secured to the framework of the automobile. The retaining clip also has a pair of head projections that extend laterally from the top ends of the respective legs and a pair of detent structures that also extend laterally from exterior surfaces of the respective legs at a predetermined distance from the head projection of each of those legs. Each of the legs of the retaining clip has a tab aperture formed therethrough within which is disposed a retaining tab. These retaining tabs are essentially cantilever structures, are inclined inwardly from the legs of the retaining clip, and may be deflected to permit the blade fastener to be received between the legs of the retaining clip. The tips of the retaining tabs are constructed and arranged to engage an aperture formed through the blade fastener in such a manner as to prevent the withdrawal of the blade fastener from between the legs of the retaining clip. The retaining tabs oppose any forces applied to the blade fastener that would tend to withdraw the blade fastener from within the retaining clip substantially in compression. Note that the hold that the retaining tabs maintain upon the blade fastener exceeds the strength of the hold maintained by the retaining clip on the panel into which it has been inserted. Note also that it is often desirable to be able to withdraw the retaining clip from a window in which it is seated for servicing of the panels that the retaining clip serves to connect. In this case, it may be desirable to include with the retaining clip a pair of support bars that are secured across the respective tab apertures and to the retaining tabs themselves. In this way opposing forces engendered within the retaining tabs are applied to the legs of the retaining clip nearer the bottom of the legs to reduce the outwardly directed component of the opposing forces that acts to secure the retaining clip in a window formed through a first panel.
The retaining tabs of the retaining clip of the present invention preferably form an acute angle with the blade fastener when the blade fastener has been engaged therein. In addition, the tips of the retaining tabs are constructed and arranged to either engage each other through the aperture formed through the blade fastener or to engage an edge or lip of the aperture formed through the blade fastener itself in order to offset lateral forces applied to the retaining tabs by the blade fastener.
While the preferred embodiment of the present invention has a single pair of retaining tabs, it is envisioned that the retaining clip may comprise multiple pairs of retaining tabs. In addition, the present invention may be adapted such that the blade fastener has a width much greater than its height. Such a blade fastener may be engaged by a single retaining clip having similar dimensions, or by multiple retaining clips having a single pair of retaining tabs or multiple pairs of retaining tabs. In any case, the magnitude of force required to insert the blade fastener into the retaining clip is relatively low, and typically is about two pounds.
The present invention may also be characterized as a mechanism for securing together a first and a second panel. This mechanism comprises a retaining clip that has a U-shaped body formed of a pair of legs that are flexibly connected at their bottom ends. The legs are spaced apart from one another sufficiently to receive therebetween a blade fastener that is secured to a second panel. Each of the legs has extending laterally from an exterior surface thereof a head projection and a detent structure. The head projection extends laterally from an upper end of each leg whereas the detent structure is positioned below the head projection a predetermined distance therefrom. Each of the legs also has formed therethrough a tab aperture having disposed therein a retaining tab. Each of the retaining tabs extends from adjacent the head projection inwardly toward the bottom of the legs. These retaining tabs are constructed and arranged to permit the blade fastener of the second panel to be inserted between the legs but to thereafter engage the blade fastener in such a manner that a withdrawal force applied to the blade fastener will be opposed by the retaining tabs substantially in compression. Preferably, these retaining tabs will form an acute angle with the blade fastener as the withdrawal force is applied thereto. In use, the retaining clip is first engaged with the blade fastener and the assembled mechanism is then inserted into a window formed through the second panel to secure the first and second panels together.
In another embodiment of the present invention, the tips of the retaining tabs may be notched to engage the aperture formed through the blade fastener. Alternatively, the retaining tabs may be constructed and arranged to engage a blade fastener that is provided with a series of ridges in its exterior surface in lieu of an aperture.